使用子集中的范围字符（）/从字符到数字的强制范围(Using the Character of a Range in Subset()/Coercing Range from Character to

使用子集中的范围字符（）/从字符到数字的强制范围(Using the Character of a Range in Subset()/Coercing Range from Character to Numeric)

我正在努力让subset（）函数使用一个范围（即4：7），它被称为变量中的一个字符。

有没有办法让我强制输入，即变量DayVar，并且我希望函数子集的不同日期是数字，同时避免以下问题：

1.）保持4：7而不是4,5,6,7和

2.）将字符“1：4”转换为数字格式，子集评估可以使用它，就像它是1：4一样。

这是一个示例数据框：

DayVar = c("1", "2", "3", "4:7") a <- c("a", "b", "c", "d", "e", "f", "g", "h", "i", "j") b <- c(61:70) Day <- c(1:10) df <- data.frame("a" = a, "b" = b, "Day" = Day) Subset <- list() for(i in 1:length(DayVar)){ Subset[[i]] = subset(df, Day %in% DayVar[i]) }

I'm struggling with having the subset() function use a range (i.e. 4:7) that is being called as a character from a variable.

Is there a way for me to coerce the input, which is the variable DayVar and has different days I want the function to subset, to be numeric while avoiding the following issues:

1.) keeping the 4:7 as such instead of as 4, 5, 6, 7, and

2.) converting the character "1:4" into numeric format that the subset evaluation can use as though it were 1:4.

Here is a sample data frame:

DayVar = c("1", "2", "3", "4:7") a <- c("a", "b", "c", "d", "e", "f", "g", "h", "i", "j") b <- c(61:70) Day <- c(1:10) df <- data.frame("a" = a, "b" = b, "Day" = Day) Subset <- list() for(i in 1:length(DayVar)){ Subset[[i]] = subset(df, Day %in% DayVar[i]) }

最满意答案

由于thelatemail建议列表有效，但您必须更改DayVar引号以获取列表索引：

DayVar <- list(1,2,3,4:7) Subset <- list() for(i in 1:length(DayVar)){ Subset[[i]] = subset(df, Day %in% DayVar[[i]]) }

As thelatemail suggested the list works but you have to change the DayVar quotes to get the list index:

DayVar <- list(1,2,3,4:7) Subset <- list() for(i in 1:length(DayVar)){ Subset[[i]] = subset(df, Day %in% DayVar[[i]]) }